Microstructural, optical and electrical investigations of large scale selenium nanowires prepared by template electrodeposition

Abstract

Large scale selenium nanowires have been prepared into the pores of polycarbonate track-etched membrane by template electrodeposition. X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and UV–Visible spectroscopy have been used to characterize as-prepared crop of selenium nanowires. XRD and FESEM studies confirmed the formation of dense crop of selenium nanowires with trigonal phase. The spectra exhibited a highly crystalline peak corresponding to (100) plane suggesting a preferential growth along [001] direction. Williamson–Hall analysis has been used to determine the crystallite size and micro strain induced due to lattice deformation. The band gap of as-prepared selenium nanowires has been found to be 1.76 eV and of the direct type of transition. The blue shift observed in the optical band gap of selenium nanowires has been attributed to quantum size effect in semiconductor nanowires. Electrical properties of selenium nanowires have been examined using two probe method and showed double diode like current–voltage characteristics. The possible reaction mechanism of the formation of selenium nanowires has also been discussed.